Polyvinyl ethers of beta guanylethanols



Patented June 12, 1945 my cuss Bouts, sum, N. m, asslgnor' to in. du Pont de Nemonrs a Company, Wilmington, not, a corporation olDelswaI-e No Drawing. Application mm: 2:, 194:,

Serial No.d80,ll

1: Claims. (0i. zoo-o0) This invention relates to new polymeric prod-- ucts, andniore particularly to 'a new type of polyamidine (guanyl compound).

This invention has as an'obiect the preparation 01 new basic polymeric materials. Another object is the preparation of new wetting agents. 'Other objects will appear hereinafter.

These objects are accomplished by the fol-- lowing invention of polyvinyl ethers of betahydroxypropionamidines (beta guanylethanols) and salts thereof and the preparation of the salts from polyvinyl beta-cyanoethyl ethers by reacting the same with an anhydrous alcohol and a strong, preferably non-oxidizing, inorganic:

acid followed by reaction with ammonia or a monoamine having at least one amino hydrogen. The free amidines may be obtained by treatment of the salt with aqueous alkali.

For simplicity in nomenclature the compounds The parent amidine base is obtained by treatment of the salt with aqueous alkali. The free base is soluble in ether but insoluble in the alkaline solution.

' The moreldetailed practice of the invention is illustrated by the following examples wherein parts given are by weight. There are, of course,

many forms of the invention other than these specific embodiments;

Example l .-Polyvi1wl'ether of methyl3-hydroxypropiomimidate hydrochloride Forty-nine of polyvinyl beta-cyanoethyl ether was dissolved in -280 parts of anhydrous triiuging, whereupon two layers formed, which became a homcgenous solution upon the addiobtained may also be referred to as polyvinyl of mm (50% excess) of absolute math-9" ethers of beta-guanylethanols. p

In preparing the imino ether salt of a polyvinyl beta-cyanoethyl ether the latter is dissolved in a suitable solvent such asanhydrous methyl acetate. The two liquid layers which form become a single layer when an amount of anhydrous alcohol 50% in excess of that required to react with the nitrile group is added. The

solution is cooled to 0 C. and an amount of dry hydrogen chloride 10% in excess or that equivalent to the nitrile groups present, is addedduring aperiod of. about 45 min. The resulting clear solution is stored at a temperature oi about 5 C. In about three hours the imino-ether hydrochloride begins to separate as an oil which after another 16 hours at 5 C. becomes a tough rubbery precipitate. Aiter decanting the methyl acetate, the polymer is rinsed several times with anhydrous ether and dried .at low temperaturein a vacuum over phosphorus pentox'ide.

. 40 The imino-ether hydrochloride, which llhygroscopic and unstable at elevated temperatures. is converted to an amidine by dissolving the same in a suitable solvent such as anhydrous methanol and adding, with thorough'mixing, an .excess (10%) of a primary or secondary amine or ammonia. The solution is allowed to react'at vroom temperature for 16-44 hours. The solvent is then removed by distillation under reduced pressure, leaving a thick syrupy or tally-like polymeric product which is rinsed several times with anhydrous ether and dried at reduced presnol. The solution was cooled to 0 C., and 20 parts of dry hydrogen chloride was run in during a period oi minutes.- The resulting clear,

separate out as an oil which overnight became a tough rubbery precipitate. After decanting the methyl acetate, the polymer was rinsed several times with anhydrous ether and'dried in a vacuum over phosphorus pentoxide. A yield of 73 parts (88% of the theoretical) of a pink, hygroscopic material was obtained. It was soluble in I water (but the amide precipitated upon standa ing' for a few minutes), methanol and ethanol,

and was insoluble in ether, methyl acetate, ethyl acetate, 'dioxane, benzene, and toluene. This product was used immediately after synthesis tor the subsequent conversion to amidine.

Immple IL-Polyoinyl ether of methyl i -hydrosypropionimidate hydrochloride To a solution or 24 parts of polyvinyl betato 0-5 0., was added slowly, with vigorous stirring, is parts excess) of dry-hydrogen chloride. After the addition of the chloride was complete, 18 parts (100% excess), gooiabsolutemethanolwasaddedandthereactioitmixturcwasthenstoredat0-5"(tier:v

days at which time the reaction mixture was 7 dark red-brown in color. The iminoether hydrochlorideisolsted rromthisreaction mixture was lesoiublcinwstsr.

Ezample [IL-Polyvinyl ether of .i-hydrorypropionamidine hydr Seventeen parts of the polyvinyl ether of methyl a-hydroxypropionimidate hydrochloride (prepared as described in Example I) was dissolved in a solution oi 8.5 parts of anhydrous ammonia in 91.5 parts of absolute alcohol at room temperature (about 25 C.) and allowed to stand at this temperature for 16-20 hours. The alcohol was evaporated from the reaction mixture and'tho residue washed with several portion of anhydrous etherand dried .in a vacuum over phosphorus pentoxide. Twelve and live-tenths parts (83% of the theoretical) of a light peach colored Product was obtained. It was soluble in water and alcohols and in aqueous sodium hydroxide.

Example IV.Polyoinul ether of 3-hydrory-N- butyl-propionamidine hydrochloride A solution of 12 parts of polyvinyl ether of methyl 3-hydroxypropionimidate hydrochloride in 79 parts of absolute methanol was mixed thoroughly at room temperature with a solution of 6 parts of normal butylamine in 40 parts of absolute methanol. The reaction mixture was allowed to stand at room temperature for 16-20 hours and then the methanol was removed under reduced pressure at a temperature not higher than 55C. A syrup-like product was obtained which was washed several times with anhydrous ether and dried in a vacuum over phosphorus pentoxide. The product was a pink hygroscopic polymer amounting to 13 parts (87% of theoretical) which was soluble in alcohol and water. Treatment of this amidine salt with aqueous sodium hydroxide solution precipitated the basic amidine which was soluble in ether.

Example V.'Polyotnyl ether o! S-hydroru-N dodecyl-propionamidine hydrochloride A solution 0! 17 parts of the polyvinyl ether of methyl 3-hydroxypropionimidate hydrochloride in 40 parts of absolute methanol was mixed thoroughly with 21 parts of n-dodecylamine in 40 parts of absolute methanol and allowed tostand at roomtemperature for-i640 hours. From this reaction mixture there was isolated by the procedure used in the preceding example 27 parts of a slightly orange colored productwhich was soluble in water and methanol but insoluble in ether. Treatment of the amidine hydrochloride with aqueous alkali precipitated .the tree amidinc base (guanylalkanol ether).

The polyvinyl beta-cyanoethyl ethers employed may be prepared by theprocess of my copending application Serial No. 463,847, tiled- October 29, 1942, the disclosure of which is hereby incorporated herein, and include not only the'beta-cyanoethyl ethers of homopolymsric vinyl alcohol but also copolymers thereof con- .taining the polyvinyl alcohol group CH(OH) CH:-

copoiymerized-with other groups. 1o!r mi for example, copolymers of: acrylic acid, alkyl substituted acrylic acids, e. g.. methacrylic acid.

yl methacrylate, acrylonitrile, and acrylamide;

vinyl aryls such as styrene; other vinyl esters,

e. g., vinyl chloride and vinyl chloroacetate, and the like. In short, any polyvinyl compound containing a plurality of free hydroxyl groups, with or without combined hydroxyl groups or other groups, may be reacted with vinyl cyanide in accordance with the process of my said copending application to obtain the polyvinyl beta- ,cyanoethyl ethers employed in the process of the present application.

These polyvinyl beta-cyanoethyl others whether derived from homopolymeric polyvinyl alcohol or' copolymers thereof are characterized by the presence or recurring units of the formula and the amidine salts derived therefrom, i. e., the polyvinyl ethers of beta-guanyl ethanols are all polymers having a plurality of recurring units of the formula wherein X is the non proton radical of a mineral acid of ionization constant of at least 1x10" at 25 C. and R1 and R2 are hydrogen or monovalent hydrocarbon radicals, preferably alkyl, and which amldinesalts may be converted to the corresponding amidines by treatment with an alkali.

While in the first step of the present process, the formation of the imino-ether from the cyanoether, any alcohol may be employed, longer reaction times are needed with alkanols oi more I than two carbons than is the case when an alkanol of up to two carbon atoms, 1. e., methanol or ethanol, is employed. The latter are therefore preferred.

The examples disclose the use oi hydrogen chloride, but any anhydrous strong, i. e., of ionization constant of at least lxlilat 25 0., preferably non-oxidizing, mineral acid may be employed'including hydrogen bromide, sulfuric acid, phosphoric acid, etc.

The relative amounts of ingredients employed may be those of stoichiometric equivalents. However, it is preferred to use a slight excess of alcohol and inorganic acid in order to obtain complete reaction of the polyvinyl alcohol. The diluentfor this step of the reaction may be any inert liquid which dissolves the starting materials at least partially, and which does not react with any of the starting materials. The preferred dilu-, ents are methyl acetate and acetone, although others may be used.

The temperature at which the reaction is conducted is maintained suiilciently low to avoid momposition of the iminoethcr salt. Thus, it is necessary to operate below 129' C. and preferably at about 0-5 G. The reaction may be carried out at subatmospheric, atmospheric, or superatmospheric pressure.

In the second step of the process, the conversion 0! the iminoether salt to the amidine salt,

the examples illustrate the use of ammonia and a two primary amines.

However, any ammonia type compound having at least one hydrogen on ammonia type nitrogen and only one nitrogen atom the valences of which not satisfied by hydrogen atoms are satisfied by and their esters, nitriles, and amides. c. g., meth monovalent hydrocarbon radicals, preferably aliphatic and preferably saturated, may be employed, including ammonia, saturated amines,

-e. g., n-butylamine, n-dodecylamine, methyl-.

amine, dimethylamine, n-propylamine, and namylamine; unsaturated amines, e. g., allylamine; and aromatic amines, e. g., aniline and methylaniline. Primary alkylamines are the preferred amines. Primary amines are preferred to secondary amines since the reaction with the latter is slower. In the second step the diluent eflects a homegenous solution of the reactants and should, therefore, dissolve the reactants at least to a slight extent and should be inert to them. The preferred solvents are the lower aliphatic alcohols such as methanol and ethanol. A slight excess (IO-25%) of amine over that chemically equivalent to the iminoether salt which is used is advantageous in obtaining more complete reaction of the polyvinyl iminoether The temperature at which the second stage of the reaction is conducted is maintained sumcientiy low to avoid decomposition of the imlnoether salt. Thus, it is necessary to operate below 120 C. and preferably at 20-30 C. Any temperature below 50 C. issatisfactory. as long as it is sufiicient to allow reaction to take place. The reaction may be carried out at subatmospheric, atmospheric, or superatmospheric pressure.

The products of this invention are useful as wetting agents. The process of this invention is useful as a means of preparation of hitherto unknown compositions of matter.

The above description andexamples are intended to be illustrative only. Any modification of or variation therefrom which conforms'to the spirit of the invention is intended to be included within the scope of the claims.

What is claimed is:

1. A process for the preparation ofthe polyvinylether of beta-guanylethanol which comrises reacting polyvinyl betacyanoethyl ether in ether: of beta-guanylethanois which comprises reacting at a temperature below the decomposition temperature and below, 120- C. a polyvinyl betacyanoethyl ether in an anhydrous inert diluent with an alcohol of up to two carbon atoms and a strong mineral acid and reacting the resuiting imino ether with a tervalent nitrogen compound having theone nitrogen atom attached to at least one hydrogen atom, the valences of said nitrogen atom-not satisfied by hydrogen being satisfied by alkyl.

4. A process for the preparation of the Polyvinyl ether of a beta-guanylethanol which comprises reacting at a temperature below the decomposition temperature and below 120 C. poly-- vinyl betacyanoethyl ether in an anhydrous diluent with an alcohol of up to two carbon atoms and a strong mineral acid and reacting the resulting imino ether with, a tervalent nitrogen compound having the one nitrogen atom attached to at least one hydrogen atom, the valences of said nitrogen atom not satisfied by hydrogen being satisfied by alkyl.

5. In a process for the preparation of the polyvinyl ether of a beta-guanylethanol the step which comprises reacting at a temperature below by monovalent hydrocarbon radicals.

anhydrous methyl acetate at 0 C. with anhydrous methanol and hydrogen chloride, isolating the resulting polyvinyl ether of methyl 3-hydroxypropionimidate hydrochloride and reacting the same at 25 C. with anhydrous ammonia-in absolute ethanol.

2. A process for the preparation of the poly-- 3. A process for the preparation oi polyvinyl guanylethanol.

6. Process of claim 5 wherein the tervalent nitrogen'compound is aprimary alkylamine.

7. Process of claim 5 wherein the ether is reacted with ammonia.

8. An ether of a polyvinyl alcohol with a 'beta-' guanylethanol wherein the valences of the nitrogen's not satisfied by hydrogen, the anion, and 4 9. An ether of polyvinyl alcohol with a betagu'arwiethanol wherein the valences of the nitrogens not satisfied by hydrogen, the anion, and the guanyl carbon are satisfied by monovalent hydrocarbon radicals.

10. The polyvinyl ether of beta-guanylethanol. 11. The

12. The polyvinyl ether or guanylethanol. l

13. The polyvinyl ether of an N-aIkyl-betemy cams nou'rz.

polyvinyl ether -.of N-butyl-beta-' N-dodecyl-beta- Y 

